A highly sensitive and specific combined clinical and sonographic score to diagnose appendicitis.

BACKGROUND: Computed tomography (CT) scanning reduces the negative appendectomy rate however it exposes the patient to ionizing radiation. Ultrasound (US) does not carry this risk but may be nondiagnostic. We hypothesized that a clinical-US scoring system would improve diagnostic accuracy. METHODS: We conducted a retrospective review of all patients (age, >15 years) who presented through the emergency department with suspected appendicitis and underwent initial US. A US score was developed using odds ratios for appendicitis given appendiceal diameter, compressibility, hyperemia, free fluid, and focal or diffuse tenderness. The US score was then combined with the Alvarado score. Final diagnosis of appendicitis was assigned by pathology reports. RESULTS: Three hundred patients who underwent US as initial imaging were identified. Thirty-two patients with evident nonappendiceal pathology on US were excluded. In 114 (38%), the appendix was not visualized and partially visualized in 36 (12%). Fifty-seven (21.3%) had an appendectomy with 1 (1.7%) negative. Six nonvisualized appendicies underwent appendectomy, with no negative cases. Sensitivity and specificity for the sonographic score were 86% and 90%, respectively, at a score of 1.5. The combined score demonstrated 98% sensitivity and 82% specificity at 6.5, and 95% sensitivity, and 87% specificity at a score of 7.5. Sensitivity and specificity were confirmed by bootstrap resampling for validation. Area under receiver operating characteristic (ROC) curves for our new US score were similar to the ROC curve for the Alvarado score (91.9 and 91.1, p = 0.8). The combined US and Alvarado score yielded an area under the ROC curve of 97.1, significantly better than either score alone (p = 0.017 and p < 0.001, respectively). CONCLUSION: Our scoring system based entirely on US findings was highly sensitive and specific for appendicitis, and it significantly improved when combined with the Alvarado score. After prospective evaluation, the combined US-Alvarado score might replace the need for computed tomography imaging in a majority of patients. LEVEL OF EVIDENCE: Diagnostic Test, Level III.

The Role of Report Comparison, Analysis, and Discrepancy Categorization in Resident Education.

OBJECTIVE: The purpose of this study was to show the value of automated radiology report comparison and analysis in resident education by providing qualitative and quantitative feedback on the discrepancies between preliminary and finalized reports. MATERIALS AND METHODS: Anonymous surveys on dictation practices and the process of reviewing reports were completed by consenting radiology residents and faculty. All 277 reports obtained across all modalities during the 4-week study were retrieved from the dictation server in both their preliminary and finalized states, for a total of 544 reports. Disparities between these reports were automatically compared side by side and were categorized according to clinical relevance, report quality, or report structure. The frequency of report corrections was compared between junior (postgraduate years [PGYs] 2 and 3) and senior (PGYs 4 and 5) residents. Residents were surveyed regarding the usefulness of the feedback. RESULTS: Eighty-six reports (31%) were verified as unchanged, with no statistically significant difference noted between junior and senior residents (33.2% and 25.9%, respectively; p = 0.03). Of the 370 discrepancies noted in the 191 edited reports, 81 (21.9%) were discrepancies in clinically relevant findings; 106 (28.6%) were discrepancies in report quality; and 183 (49.5%) were discrepancies in report structure, syntax, or both. Although senior residents had a lower rate of discrepancies in the clinical relevance category than did junior residents (12.8% and 26.5%; p = 0.004), they had a higher rate of discrepancies in the report quality category (58.4% and 44.9%; p = 0.02). Surveys of both residents and faculty showed strong support for the project. CONCLUSION: Categorization of corrections was deemed useful by residents and can be helpful in assessing elements of reporting accuracy for individual feedback. Quantitative report comparison and analysis show promise in tailoring resident education at the programmatic level as cumulative data are gathered and trends are analyzed.

The floating cardiac fat pad-sign of occult pneumothorax.

Pneumothoraces are a possible sequela of chest trauma with potential morbidity and mortality if not recognized and treated promptly. A portable supine chest radiograph is frequently the first radiologic study performed in the setting of trauma. While large pneumothoraces can be readily recognized on these radiographs, smaller pneumothoraces are missed in up to 15 % of trauma patients. There are many radiographic signs of occult pneumothoraces, and we are presenting a new radiographic sign of occult pneumothorax. The floating cardiac fat pad sign occurs when pleural air collects anteriorly and superiorly in the most non-dependent portion of the chest lifting the pericardial fat pad off the diaphragm. Lung markings are still seen surrounding the pericardial fat pad due to the inflated lower lobe of the lung resting dependently. Rapid and accurate identification of pneumothoraces is critical but often difficult on chest radiographs. Although there are many existing radiographic signs for identification of pneumothorax, prospective identification of small pneumothoraces is still relatively poor. Here, we describe an additional sign which aides in the detection of pneumothoraces, the floating cardiac fat pad. When present, this should prompt further evaluation with chest CT or upright chest radiograph.

Completion CT of Chest, Abdomen, and Pelvis after Acute Head and Cervical Spine Trauma: Incidence of Acute Traumatic Findings in the Setting of Low-Velocity Trauma.

PURPOSE: To determine the frequency of acute traumatic findings in computed tomographic (CT) chest abdomen pelvis (CAP) examinations in patients with acute traumatic head and/or cervical spine injury and no evidence suggesting bodily injury. MATERIALS AND METHODS: After institutional review board approval with a waiver of informed consent was obtained, a HIPAA-compliant retrospective study was performed. A review of the electronic medical records and dictated reports identified patients who met the following criteria: CT-documented acute head and/or cervical spine trauma, CT CAP performed at least 20 minutes after initial brain and/or cervical spine CT, and no evidence of bodily injury at physical examination or on initial plain radiographs. The types of head and/or cervical injury, as well as mechanisms of injury in these patients, were analyzed. The frequency of acute traumatic injury in the CT CAP examinations was also determined, and 95% confidence intervals were calculated. RESULTS: There were 115 patients who met the study criteria (average age, 67.3 years). Sixty-three (54.8%) patients were male. The average injury severity score was 9.3. No patients who met the criteria for this study were found to have an acute traumatic injury to the chest, abdomen, or pelvis. These 115 CT CAP examinations comprised 7.5% (115 of 1530) of all CT CAP examinations performed in the emergency department over the 15-month study period. CONCLUSION: CT CAP examinations rarely if ever reveal acute traumatic injury in patients who have experienced low-velocity trauma and have acute head and/or cervical spine trauma in the absence of evidence of bodily injury.

Reshaping the emergency radiology call experience after the merger of two programs: the Yale experience.

In the summer of 2013, 16 radiology residents from the Hospital of Saint Raphael (HSR) joined the 38 residents of Yale-New Haven Hospital (YNHH) to become a single 54-resident program. This posed a significant challenge given the number of residents and very different call structures of the two institutions. After evaluating the emergency radiology volume at both hospitals, it was determined that implementing YNHH's traditional call system at HSR would increase call by approximately 25 %. In order to negate this increase, the SRC rotation was created at HSR. This Monday-Friday rotation covered by R3s starts at 1 p.m. with afternoon conference. Residents then read cases on a subspecialty service from 2-5 p.m. and then cover the entire hospital until 10 p.m. with a single attending. Because of this rotation, call did not increase for the YNHH residents and third year residents were provided with increased responsibility. For programs not undergoing a merger, call rotations can also be extremely beneficial. These rotations allow third year residents to have more "call-free" weeks prior to the ABR core exam. Also, patient care can be improved, as the shift length for on-call residents is reduced, which has been shown to improve accuracy.

Impact of adaptive statistical iterative reconstruction on radiation dose in evaluation of trauma patients.

BACKGROUND: A recent study showed that computed tomographic (CT) scans contributed 93% of radiation exposure of 177 patients admitted to our Level I trauma center. Adaptive statistical iterative reconstruction (ASIR) is an algorithm that reduces the noise level in reconstructed images and therefore allows the use of less ionizing radiation during CT scans without significantly affecting image quality. ASIR was instituted on all CT scans performed on trauma patients in June 2009. Our objective was to determine if implementation of ASIR reduced radiation dose without compromising patient outcomes. METHODS: We identified 300 patients activating the trauma system before and after the implementation of ASIR imaging. After applying inclusion criteria, 245 charts were reviewed. Baseline demographics, presenting characteristics, number of delayed diagnoses, and missed injuries were recorded. The postexamination volume CT dose index (CTDIvol) and dose-length product (DLP) reported by the scanner for CT scans of the chest, abdomen, and pelvis and CT scans of the brain and cervical spine were recorded. Subjective image quality was compared between the two groups. RESULTS: For CT scans of the chest, abdomen, and pelvis, the mean CTDIvol (17.1 mGy vs. 14.2 mGy; p < 0.001) and DLP (1,165 mGy·cm vs. 1,004 mGy·cm; p < 0.001) was lower for studies performed with ASIR. For CT scans of the brain and cervical spine, the mean CTDIvol (61.7 mGy vs. 49.6 mGy; p < 0.001) and DLP (1,327 mGy·cm vs. 1,067 mGy·cm; p < 0.001) was lower for studies performed with ASIR. There was no subjective difference in image quality between ASIR and non-ASIR scans. All CT scans were deemed of good or excellent image quality. There were no delayed diagnoses or missed injuries related to CT scanning identified in either group. CONCLUSION: Implementation of ASIR imaging for CT scans performed on trauma patients led to a nearly 20% reduction in ionizing radiation without compromising outcomes or image quality. LEVEL OF EVIDENCE: Therapeutic study, level IV.

Introducing medical students to radiology as paid emergency department triage assistants.

PURPOSE: The aim of this report is to provide a detailed description of a program employing medical students to assist with triaging off-hour diagnostic imaging studies at a major academic medical center. METHODS: Current and former participants of the Medical student Emergency Department (ED) Radiology Triage Program were interviewed regarding the inception, development, and impact of this program. Student participation and triage activities were compiled and tabulated from scheduling records and triage assistant call logs. RESULTS: Opportunities for medical students to obtain an intensive, well-organized experience in radiology are often absent or occur relatively late during medical school, which can be problematic for developing basic imaging literacy and for making timely, well-informed decisions regarding radiology as a career path. The authors describe a program that provides students with a rigorous, hands-on experience in radiology relatively early in their training by employing medical students to assist the emergency department radiology staff with managing off-hour radiology workflow. Students work with the off-hour emergency department radiologists and staff members answering phone calls and help to facilitate the ordering and protocoling of studies and the dissemination of results to clinicians. CONCLUSIONS: The employment of medical student triage assistants provides in-depth exposure to clinical radiology relatively early in medical school, while providing an effective system to help streamline the off-hour workflow for attending radiologists, residents, technicians, and support staff members.

Development of a computed tomography-based scoring system for necrotizing soft-tissue infections.

BACKGROUND: Necrotizing soft-tissue infections (NSTIs) are associated with significant morbidity and mortality, but a definitive nonsurgical diagnostic test remains elusive. Despite the widespread use of computed tomography (CT) as a diagnostic adjunct, there is little data that definitively correlate CT findings with the presence of NSTI. Our goal was the development of a CT-based scoring system to discriminate non-NSTI from NSTI. METHODS: Patients older than 17 years undergoing CT for evaluation of soft-tissue infection at a tertiary care medical center over a 10-year period (2000-2009) were included. Abstracted data included comorbidities and social history, physical examination, laboratory findings, and operative and pathologic findings. NSTI was defined as soft-tissue necrosis in the dictated operative note or the accompanying pathology report. CT scans were reviewed by a radiologist blinded to clinical and laboratory data. A scoring system was developed and the area under the receiver operating characteristic curve was calculated. RESULTS: During the study period, 305 patients underwent CT scanning (57% men; mean age, 47.4 years). Forty-four patients (14.4%) evaluated had an NSTI. A scoring system was retrospectively developed (table). A score >6 points was 86.3% sensitive and 91.5% specific for the diagnosis of NSTI (positive predictive value, 63.3%; negative predictive value, 85.5%). The area under the receiver operating characteristic curve was 0.928 (95% confidence interval, 0.893-0.964). The mean score of the non-NSTI group was 2.74. CONCLUSIONS: We have developed a CT scoring system that is both sensitive and specific for the diagnosis of NSTIs. This system may allow clinicians to more accurately diagnose NSTIs. Prospective validation of this scoring system is planned.